Tweet
I was contacted offline by someone who has a particular noise in his older (circa 1980-81) Deluxe Memory Man, and we are having troubling narrowing down the source, and whether it is fixable. We have already had some back and forth, and it appears both the bias trimpots, and the balance trimpot have been set correctly, so we know it's not those things. I was wondering if the compander was amiss (i.e., not perfectly symmetrical in its action), hence point #6.
Any ideas for what the deal is would be deeply appreciated.
He writes:
"Well, I just had some very good listen to the pedal with fresh ears and here is what I've found:
1.....The "buzz" can also be describes as a "scratch", almost like on an old vinyl record.....sort of undefined sound...(ring modulator like but not as complex, yet more complex than a single pitch)
2.....This sound does get louder as you increase delay time and and weaker as you decrease it.
3....Feedback settings don't affect it. I hear it the same with only one repeat or many more.
4.....The sound is present on the first repeat and even though it's difficult to say this with certainty, it seems to be present on the first repeat ONLY.
It's possible that it's also present on the second repeat but due the second one being less loud than the first one, so does that sound.
5.....The sound is somewhat related to the pitch you play on the guitar....or more correctly put, some pitches bring it out more. With the current Balance trim setting, the sound comes out most when you play the "G" at the 8th fret on the 2nd string and is also very noticeable a few frets up or down.
6.....The dynamics of the Delay line seems normal as you hear the white noise track the delay when you play.
Would you think that it's possible some old caps somewhere could be related to the problem?
I did not trace the circuit of this pedal but it seems to be from 80-81 as the pots have that time period date codes. All the chips have what looks like 78-79 date codes.
I attached the schematic that I have for an "old original" DMM.
I hope all of this might give you some insight into the problem.
Any ideas for what the deal is would be deeply appreciated.
He writes:
"Well, I just had some very good listen to the pedal with fresh ears and here is what I've found:
1.....The "buzz" can also be describes as a "scratch", almost like on an old vinyl record.....sort of undefined sound...(ring modulator like but not as complex, yet more complex than a single pitch)
2.....This sound does get louder as you increase delay time and and weaker as you decrease it.
3....Feedback settings don't affect it. I hear it the same with only one repeat or many more.
4.....The sound is present on the first repeat and even though it's difficult to say this with certainty, it seems to be present on the first repeat ONLY.
It's possible that it's also present on the second repeat but due the second one being less loud than the first one, so does that sound.
5.....The sound is somewhat related to the pitch you play on the guitar....or more correctly put, some pitches bring it out more. With the current Balance trim setting, the sound comes out most when you play the "G" at the 8th fret on the 2nd string and is also very noticeable a few frets up or down.
6.....The dynamics of the Delay line seems normal as you hear the white noise track the delay when you play.
Would you think that it's possible some old caps somewhere could be related to the problem?
I did not trace the circuit of this pedal but it seems to be from 80-81 as the pots have that time period date codes. All the chips have what looks like 78-79 date codes.
I attached the schematic that I have for an "old original" DMM.
I hope all of this might give you some insight into the problem.
Comment